according to my graphic designer friends, its 1 space only after a period. this is because the font designer takes all this into account and makes the space be the appropriate size between a period and start of the next sentence.

i got the opinion that the typewriter standard of 2 spaces drives them nuts because the uninformed are all still putting 2 spaces even when using a computer! Opps! (hehe)

Depends, actually. When preparing text-only docs with a monospaced font (e.g. Courier), it's still a good idea to use two spaces. Otherwise, one space is the way to go as proportional fonts are designed to use the appropriate amount of space required by
each character. (Confession: I'm a recovering graphic designer!)

I definitely fall into the double-space category. Although after listening to Bill, I can see where things like this and underlining items definitely dates my typewriter training to my high school days.

I think now I will be more self-conscious of when I use formating tools like that.

Me too. Underlined links, or more precisely, links that don't obey the browser's Underline links setting (which I set to "Hover", btw) are my pet usability peeve because I have difficult reading underlined text.

Bill's right, by the way. Underlining came about because it wasn't feasible to put
italics on a typewriter, and two spaces after periods came about because typewriters only had one size "space", and thus, couldn't duplicate an "em" space.

A couple of months ago I was asked to review an internal memo by one of our group managers. I sent him assorted feedback, but the biggest thing I pointed out was the need for a single space after each period. He was actually using three!

When my GM pushed me for a reason, I told basically the same thing that Bill said: go to your bookshelf, pull a book, and count the number of spaces. You'll only find one.

If Bill's comments above fascinate you, I suggest checking out the book The Elements of Typographic Style by Robert Bringhurst. It's a great and fun introduction to the world of typography, and yes, there's even a discussion on spaces after periods.

I don't quite catch your argument, Bill, that the 2 space issue is different in a digital typesetting environment versus typewriters and classical typesetting.

I agree with the underlining aspect. I can see how with typewriters and typesetters, it was easier to underline than to emphasize in other ways.

But as far as the one versus two space theory, the difference is the same with digital typesetting as with classical. Two spaces gives a clearer delineation between sentences in the same way as two carriage returns gives a clearer delineation between two paragraphs.

Some have said that modern technology (a good font designer, proportional fonts, etc) provides the same value as two spaces. This is not the case. I type a document in MS Word, and regargless of font, the difference between one and two spaces after a period
is clear. That HTML automatically compresses two (or more) spaces into one is not the technical equivalent to having two spaces after a period on a typewriter. It's the simple compression of two (or more) into one.

I'm not arguing that two spaces is better than one. I'm just arguing that two spaces in classical typesetting is the same as two spaces in modern text.

I pose two questions, then.

1) Am I wrong that the two are equivalent? No examples have been shown to the contrary, IMHO.

2) Is two spaces no longer the preferred format? I was taught otherwise, and always include two spaces. What's the advantage of a single space? I see a clear advantage in two spaces, particularly after question marks, to provide a gross visual cue to the
end of the thought without the need to recognize the delineating character. Additionally, two spaces provides the same differentiating effect with respect to the comma, which is a very visually similar punctuation.

But what's the point of two spaces? The dot (period or full-stop - depending where you come from) is supposed to put a stop of just under a second in, and when I read something with two spaces after the dot, I find myself waiting for two seconds or more
before continuing (I tend to let my semi-subconcious to the word processing, rather than thinking about it
myself).

I recently began using two spaces, again, after years of using one space. I switched because I found that Word's grammar checker can use two spaces to distinguish between a period in the middle of a sentence and a period that ends a sentence much better
if I set it to two-space mode! I am trusting in the rendering engine to properly adjust the space to look nice to the reader.

In this situation, two spaces carries a semantic meaning that is different than one space.

P.S. When is someone going to figure out how to allow me to use ink to compose comments on web pages?

I studied calligraphy and paleography in college (a blessed liberal arts education) and spent quite a bit of time with typography and type design. In a proportionally spaced font, the font designer has already allowed for the proper amount of whitespace after
a period and before the next letter. Adding a second space utterly destroys the font designer's intentions.

But don't just take our word for it. I am holding in my hand the names of 39 card carrying members of the ... whoops, sorry, wrong document. Let's try that again.

I am holding in my hand Robert Bringhurst's elegant and indispensable tome "The Elements of Typographic Style," version 2.4 (Hartley & Marks, Publishers, 1992, 1996, 2001.) Quoting from the back cover, "Robert Bringhurst is one of North America's most highly
regarded typographers and bood designers, as well as one of Canada's best-known poets. He has taught literature, art history and typographic history at several universities and held fellowships from the Canada Council for the Arts, the Social Sciences and
Humanities Research Council of Canada, and the Guggenheim Foundation." The book is also highly praised by two of the greatest legends in typographic and book arts today, Hermann Zapf and David R. Godine. In other words, Robert Bringhurst is eminently qualified,
and knows of what he writes.

On page 28, Mr. Bringhurst writes:

2.1.4 Use a single word space between sentences.

In the nineteenth century, which was a dark and inflationary age in typography and type design, many compositors were encouraged to stuff extra space between sentences. Generations of twentieth-century typists were then taught to do the same, by hitting the
spacebar twice after each period. Your typing as well as your typesetting will benefit from unlearning this quaint Victorian habit. As a general rule, no more than a single space is required after a period, a colon or any other mark of punctuation. Larger
spaces (e.g., en spaces) are themselves punctuation.

End quote.

I know you imprinted in Mrs. Barker in eighth grade typing class, and she insisted on the two-space rule. But she was wrong. Just a quaint Victorian habit. Sorry it didn't work out.

Bravo, Bill. If this is the only thing that Channel 9 accomplishes, it will be worth it.

This is utter craziness. Use two spaces. You may as well try to reform Gaelic spelling as stop the world from double-spacing. Let the font designers fix their fonts to match the typing habits of the world, not the other way around.

The convention of typists using two spaces after a full stop only came about because of the limitations of the fixed spacing for characters and spaces. Whether it should persist depends entirely on what you're typing into. If it's a fairly dumb piece of
software, which interprets a space as "add this much white space", then it may or may not be appropriate to use two spaces. If it's something which will lay the document out (such as TeX or LaTeX), then clearly there's no need. While we're wedded to documents
containing layout markup rather than functional markup I guess double spacing will persist. Dunstan

I'm defiantly a two spacer. Most of what I type is unformatted monospaced text (code and email) and when I do format things it is in some thing that doesn't care such as LaTeX. When I type things in I intend them to be interpreted as data (I don't use Word)
before they are displayed. The computer should do the work of figuring out how it should be set to look nice. Meanwhile while it is still monospaced code, it has nicely separated sentences.

I've been having this argument with my boss for years. Still haven't been able to convince him even after showing him example after example. He's English so maybe hearing it from another UK'er would make him finally accept it. Of course Bill's a Scot.
Not sure what the political ramifications would be or if it would color his perceptions. Oh well. I'll just keep using "find and replace" to change double spaces to single spaces. All in the interest of World peace you understand...

I agree with Bill--use just one space after a period. But, we're using selective rules to justify our use of a single space.

If the reason to use one space is that we shouldn't be constrained by old fashioned type rules in our digital typeset age, why then do we follow the age-old rule of putting periods inside quotation marks? There isn't much of a chance of that digital period
breaking off!

This is not just an opinion issue, it's one of readability. Good typographic fonts--not monospaced typewriter fonts--are designed with maximum readability in mind.

It's the same reason YOU DON'T WRITE LONG SECTIONS OF TEXT IN ALL CAPITAL LETTERS: YOUR EYES MOVE SLOWLY OVER THE TEXT BECAUSE IT'S HARDER TO RECOGNIZE THE INDIVIDUAL LETTERS WHEN THEY ALL TAKE UP THE SAME AMOUNT OF SPACE. (Well, that and the 'Net-savvy community
equates it with yelling!)

... we have powerfull corporations and their Product Branding and Marketting teams (with good intentions) bastardizing the basic rules of standardized and simple English sentence structure.

I love the DOT-NET technology, but the DOT-NET product branding is destroying the written form and use of the english language in the technical journals.

Here is an example sentence from the Editor's Note of MSDN Magazine, Paragraph 2 - sentence 2, April 2004 Vol 19 NO 4

"Leading off, we'll explain to you the fundamentals of code coverage in .NET. Code coverage is a way to make sure that all parts of your application are tested propertly -- it doesn't determine that they work properly, just hat they're covered by your test
suite."

The above use of '.NET.' basically invalidates ALL of Bill Hills arguements.

We already have _exceptions_ to the rules with 1.2.3.4 version numbers embedded in sentences.. now we have sentences STARTING with periods preceding Nouns. ;(

This is one reason why Homo Sapiens will never evolve beyond version 1.0.

Sorry, in today's world, single-spacing at the end of the sentence is wrong. The "." is used to connotate much more than the end of a sentence. It's used to call functions, indicate sub-releases, abbreviate, etc.

If the eye is to pick up chunks of data off the page, it has to look for meaningful glyphs / clues. The only unique clue for end-of-sentence, as far as I know, is double-spacing. Esp. in technical or terse writing. Look at that last sentence. Is "Esp."
the end of the sentence? No! It's not double spaced!

Mr. Bringhurst may have a point insofar as literature is concerned, but we have to deal with technical writing here, with a mishmash of fixed-space and (what's it called?) non-fixed-space fonts, serif and sans-serif, and so forth. What may have started
off as a "quaint Victorian habit" is today a useful and practical guideline. Furthermore, where the hell is the "en spaces" key on this damned keyboard? (And what is a "bood designer"?)

Well, for this Homo Sapiens 1.0 it's not a waste of brain cells, it's my job. And I work with a group of people who've spent their lives caring about these issues.

For proportionally-spaced fonts (that's what we call non-fixed-space) two spaces is ugly, and slows the flow.

Bringhurst's book is excellent; no, it's not just about literature. What people sometimes dismiss as "print conventions" are the result of 550 years of Darwinian evolution. There have been many experiments in type along the way. What worked, survived; what
didn't work, died.

Q. How can you tell the difference between a "desktop published" magazine or newspaper, and one that's been professionally typeset and proof-read?

A. Look for the double-spacing. Not just at the ends of sentences, but extra spaces between words. They can be hard to spot, but when proportional spacing kicks in to break a line in the right place, they often jump right out at you. And you won't even know
they're there until they do - which on the screen can depend on the size to which the person reading your text has scaled a window. Point is, you have no control.

Q. How do you quickly add value to anything you write?

A. "Replace All" double-spaces with single spaces.

Some serif faces don't work well on screen.

Times, or Times New Roman, is one of those. It was designed for print. In the print world, you have to care about cast metal letters being robust enough to withstand the pressure of a 15-ton mat press; and you also have to care about arcane things like "ink
traps" - tiny features in letters which can cause ink to collect in a small pool, and detract from print quality. basic fluid mechanics and ink viscosity had a role to play.

Ah, those were the days - when men were men, dinosaurs roamed the earth, and the average print worker carried enough lead around in his bloodstream to plumb a small condo...

But some serifs work very well.

The Verdana face in which you're reading this was one of the first projects I commissioned at Microsoft in 1995. We asked world-renowned type designer Matthew Carter to produce two new faces for Microsoft, designed to read long passages of text on screen -
especially on the Web. Verdana was the sans-serif; its lesser-known companion was the serif face Georgia.

I've written a long paper about all this, BTW. If I can figure out how to post a Word doc I'll put it up for anyone who's interested. It's called "The Magic of Reading". Or else I'll just post it in dribs and drabs (sounds like a career...)

For proportionally-spaced fonts (that's what we call non-fixed-space) two spaces is ugly, and slows the flow.

Ugly is subjective. Can you elaborate on how double-spacing slows the flow of reading, and how the effect is different with mono-spaced? Break it down, please.

bill hill wrote:

Bringhurst's book is excellent; no, it's not just about literature.

I apologize if I sounded like I was insulting Mr. Bringhurst's work. I just don't see (yet?) how double-spacing is worse, esp. considering the multitude of meanings the period has today. When I commented about literature, I'm thinking of the stuff you'll
find outside the Engineeting department of your local bookstore. You're not likely to find the following paragraph in them:

The 5.6.4.43 release of the .rc files suck. When will they finally release the 6.2 version? "Some time next month!" says the go-tool.net website. .POWER is a useful tool, but really, there are too many bugs to release it. And don't get me started on
the lack of features-- phew!

There are "."s all over the place. If I were to come to a full-stop every time I saw one, I'd go nuts. To break it down:

The 5.
6.
4.
43 release of the.
rc files suck.
When will they finally release the 6.2 version?
"Some time next month!" says the go-tool.
net website.
.
POWER is a useful tool, but really, there are too many bugs to release it.
And don't get me started on the lack of features-- phew!

Yar! That makes no sense! The period symbol is now over-overloaded, so it seems proper to use another visual or contextual clue.

bill hill wrote:

Not just at the ends of sentences, but extra spaces between words. They can be hard to spot, but when proportional spacing kicks in to break a line in the right place, they often jump right out at you. And you won't even know they're there until they do - which
on the screen can depend on the size to which the person reading your text has scaled a window. Point is, you have no control.

Not quite following you there. I mean, extra spaces between words is definately improper (it tells me the sentence just stopped), but I don't know what you mean in your example.

bill hill wrote:

It's called "The Magic of Reading". Or else I'll just post it in dribs and drabs

Great example, Stoyan. I didn't slow down while reading the code snippet, but I
did stop (often) in your text.

To rationalize this behavior to myself, I'd say that I recognized the code snippet as code (and parsed it as such, given semicolons and double-slashes their due meaning), and I stopped often in the text because the periods were in illogical places.

That said, I'm going to have to reconsider the effectiveness of a period-- did I undervalue that or the strength of sentence parsing?

For proportionally-spaced fonts (that's what we call non-fixed-space) two spaces is ugly, and slows the flow.

Could you explain how proportionally-spaced fonts has any bearing on the number of spaces to follow a sentence? On the surface, the spacing of fonts seems as if it
could affect the spacing after a sentence, but I don't see anywhere that it
does.

So far, there have been several arguments for the legitimacy of double-spacing.

The arguments against have been shallow and subjective, without any concrete evidence. You claim that two spaces slows the flow. I argue the contrary. It provides a visual cue to allow the reader to more easily differentiate the end of the sentence, allowing
the non-symantic portion of the brain to process structural information in parallel with the symantic information.

Some have claimed that "reading" that extra space takes extra time, but that can only be the case for someone who reads character by character, and I'll guarantee that 99% of the population does not read that way. The fastest readers don't even parse the text
word by word, but rather in grammatical and structural chunks.

I'd like to hear an argument for single spacing more than "it's old and we don't have to do it anymore" or "I don't like it".

bill hill wrote:For proportionally-spaced fonts (that's what we call non-fixed-space) two spaces is ugly, and slows the flow.

...

So far, there have been several arguments for the legitimacy of double-spacing.

...

Some have claimed that "reading" that extra space takes extra time, but that can only be the case for someone who reads character by character, and I'll guarantee that 99% of the population does not read that way. The fastest readers don't even parse the text
word by word, but rather in grammatical and structural chunks.

I'd like to hear an argument for single spacing more than "it's old and we don't have to do it anymore" or "I don't like it".

Besides, there's something wrong with the technology we're using, if it's not smart enough to
render the text with the appropriate amount of whitespace between sentences regardless of how many consecutive <space> characters I type. Only the computer itself need be able to discern the difference between one space and two after a sentence ending
mark.

Then again, I still refer to the Enter key as "Carriage Return," I believe lines should terminate at 80 characters as God and Herman Hollerith intended, and I expect Ctrl-G to physically ring a metal bell.

There are two books I'd highly recommend to anyone trying to understand the arcane world of type and why it's done the way it's done.

They're both published by the firm of Hartley & Marks - which I believe also publishes Bringhurst's book.

The first is called, appropriately enough, "Finer Points in the Spacing and Arrangement of Type", by Geoffrey Dowding. It's short - only about 85 pages, but it's a great read. the first time I read it I couldn't put it down, and my copy has notes all over it.
(OK, I'm the kind of warped and twisted individual who cares deeply about this stuff, I admit it...)

The second book is "The Form of the Book", by Jan Tschichold (I'm at home, my copy of this is in the office, I had to do a Websearch to make sure I spelled it right, since it's a real challenge. Pronouncing it right is an even bigger challenge. Sounds a bit
like a sneeze)

Tschichold's story is a really interesting one and highly relevant. He was, in his youth, a typographic rebel. "All text should be set in sans serif, we don't need serifs or indents at the start of paragraphs, etc etc in these modern times" (1930s).

In fact, he was actually jailed by the Nazis for being a"typographic subversive". In the same way as they tried to stamp out modern art, they tried to stamp out typographic innovation. Everything must be set in Aryan fashion - gothic blackletter. "Ve haf vays
of making you not read..."

Point is, Tschichold questioned every single typographic convention. When he got out of detention after six weeks, he left Germany for neutral Switzerland. Eventually he became the typographic expert at Penguin Books in London, at a time when it was the largest
paperback company in the world.

When he wrote this book many years later, he had returned to all the conventions he once eschewed - not because he'd gotten old and boring, but, having questioned them, he came round to understanding that they had existed for such a long time because they worked.

Sorry for the history lesson, but you can't separate type from its history. We've been doing writing systems as a race for 5500 years, and typesetting for almost 1000 (the Koreans had movable clay type in the year 1024. Gutenberg - often erroneously credited
with inventing printing, was a goldsmith and metallurgist. He invented an alloy and a method of casting as many copies of any letter as you wanted, an ink which would stick to the metal, and a press with sufficient pressure to take many impressions off the
inked type. His mechanized technology makes him the Henry Ford of printing, not the inventor).

Oh, BTW, I'd much prefer to post in justified text - but the justification in this edit window sucks big-time because there's no hyphenation. Without hyphenation, justification is totally unjustified.

Ambrose suggests that the font designers fix their fonts to match "the typing habits of the world". Say, Ambrose, have you ever looked at how a font is designed, structured and used? How would you propose changing all font technology to accomplish this?

The responses to this topic are warm, fuzzy, and (frankly) tame. How about mixing it up a little with a discussion of something innane, but strangely important, like the merits of curly-brace formatting in C, C++, C#, Java, etc. For example, should an open
curly brace be on the same line as an if/while/etc. statement, and if so, should an else be on the same line as a closing curly brace, and if so, ... (shades of homestar runner)

Oh, BTW, I'd much prefer to post in justified text - but the justification in this edit window sucks big-time because there's no hyphenation. Without hyphenation, justification is totally unjustified.

You bring back memories of when (30 years ago) I debugged computer photo-typsetting equipment; this presented a problem since the programming was in hardware.

While justifying a line, first letter-spacing would be applied to the total characters which would fit (to a point) then space-band expansion would be applied. This would be more complicated when hyphenation was turned on. Of course the rules of hyphenation
used were only accurate about 90% of the time.

OBTW, One space after periods, question marks, and exclamation points for proportional fonts is the correct usage, period.

The reason not to use two spaces has to do with creating an even typographic colour to the page. Colour here does not mean hue, but that the page has an even, consistent appearance, with nothing catching the eye and disturbing the reading process.

Bold type within text destroys colour. It makes the eye jump ahead to it. While this is fine for key points in a textbook, in a work meant to be read linearly, it steals the eye, causing the reader to visually stumble. It is not as bad in a heading, where the
eye is trained not to be surprised by the blackness (although some book designers will not use bold for heads either, to maintain colour).

A double space does the same thing, in reverse. Instead of blackness stealing the eye from the textflow, it is the whiteness of a bullet hole of white on the page. It causes the eye to jump forward to the end of the sentence to see what's caused this, and then
having to find the place it jumped from, delaying your reading by a fraction of a second.

Other ways to destroy color include using all capitals (use true small caps instead) or using lining numerals (use old style figures instead). In each case these make a blob on the page that results in slower reading.

I think the main problem is the lack of typography or design experience in the traditional schooling environment.

In just about every highschool I've seen, they teach all of the students to double-space, regardless of the font or tool (ie/ computer) being used. The teachers are generally trained in Math or Science and get the unfortunate assignment of also teaching the
"typing" or "desktop publishing" classes.

I always try to explain to people why double-spacing is (generally) not a good idea but most people refuse to change because "It's how they were taught in school".

As for the underlining issue, I personally think that there will be millions more documents with excessive underlining in the years to come. Why? Humans love variety, and sometimes people feel that Italic and Bold just aren't enough How could they let that
lovely "U" button in Word go unused?

This is deeply fascinating - for me, and many people I have talked to about the issue, single spaces after a full-stop cause innattentive reading, as they skim across sentence aftre sentence and find they have reached the end of a paragraph without actually
taking in the substance of the text.

Additionally, there is no apparent aesthetic or utilitarian benefit to the single space system. As pointed out above, the '.' is used in so many ways now that the end of sentence needs to have a clear indication over and above the dot. A single space just
doesn't cut it, even if we leave out words starting with a dot. As a quick example, I have put this paragraph in twice - it is nothing out of the ordinary as a piece of text - and would welcome honest opinions on which looks and reads better.

Additionally, there is no apparent aesthetic or utilitarian benefit to the single space system. As pointed out above, the '.' is used in so many ways now that the end of sentence needs to have a clear indication over and above the dot. A single space just doesn't
cut it, even if we leave out words starting with a dot. As a quick example, I have put this paragraph in twice - it is nothing out of the ordinary as a piece of text - and would welcome honest opinions on which looks and reads better.

I can see where the sentences are in the first version at a glance - the 'bullet holes' mentioned. But then I want to be able to get meaning out of text when I read it, and knowing how far I am about to read in one go helps this process. The double spaced
version is less threatening, because I can see that it comes in distinct parts. Perhaps it would be different if the sentences didn't all start with 'A'.

I've been a staunch double-spacer since my seventh-grade typing class, have been known to reformat text to correspond with this. This whole thread has been quite interesting; I've known Bill for a while, and his opinions on typography carry a lot of weight
with me. Whipping out a ruler and opening the nearest book convinced me that I've been reading single-spaced text just fine for probably my whole life, even though I didn't realize it. Further, it turns out my
wife converted to single-spacing years ago when she became a technical writer (I'd fathered children with a single-spacer
without even knowing it!)

What's most surprising to me is that I've converted over with relative ease -- I'd have thought that this would be hard-wired into my genes at this point, but I guess the brain is pretty good at adapting.

Interestingly, I've also converted to single-spacing my mono-sized code comments, and to no ill effect that I can see. I believe that a lot of these objections about "too many dots" are overblown, though I reserve the right to double-space if I feel it's absolutely
necessary.

I was born in England (no worries Bill, my Grandad was from Fife) and this was never ever discussed there as far as I know. I have always used one space after what we call a full-stop.

I have a couple of questions though:

1. If hyperlinks shouldn't be underlined (except per hover), which emphasis can be used in your opinion? Italic destroys small fonts, bold, as someone said (I think Bill) destroys the "whole picture" and using different colours can be too subtle sometimes and
also destroy the flow.

2. This is something I have never been sure of.
If I write "...he danced quite often...according to his brother, he was seventeen at the time..." - how do I use the "..."; should I have a space before or after the "..."?

Could you explain how proportionally-spaced fonts has any bearing on the number of spaces to follow a sentence? On the surface, the spacing of fonts seems as if it
could affect the spacing after a sentence, but I don't see anywhere that it
does.

You naturally read mono-spaced text slower because your eyes can't easily "see" word and sentence shapes with them. To some exent double spaces help you to differentiate between words and sentences.

Proportional fonts are much more natural and your eyes can more easily identify the shape of words, as such you don't need the additional space, it just slows your reading further.

jaraco wrote:

Some have claimed that "reading" that extra space takes extra time, but that can only be the case for someone who reads character by character, and I'll guarantee that 99% of the population does not read that way. The fastest readers don't even parse the text
word by word, but rather in grammatical and structural chunks.

Actually nobody (except small children maybe) reads like that. We recognize the shapes of words much more than the letters within them.

Good video Bill, I learned typing on a typewriter and it took me forever to break the habits of two spaced. I still use underlines in the title of a roughdraft and stuff like that but on a professional report or article I do use Bold or italics for the
title,

I like the look of them, even tho they're wrong. I prefer to be wrong, sometimes. For that matter, when writing database text to the output stream, I replace spaces with &nbsp;s to make sure they are represented as the typist entered them.

Perhaps it's because I've been reading voraciously for almost 40 years now, but I can't remember the last time I felt 'threatened' by a block of text. Content, yes, but just the look of it? No.

Conversely, because I am so used to reading fairly quickly (though I admit I do still hear the words in my head), I found the two-space version of your paragraph irritating compared to the more familiar one-space version. I mean irritating like a mental itch,
not irritating like a pet peeve. The visual interruption was rather like listening to someone with a silent stutter--waiting for the next thought made me more and more impatient.

One thing I think people misunderstand when they advocate for two spaces is that a paragraph is a series of connected thoughts, not just a collection of discreet statements. When the flow of those connected thoughts is interrupted visually, it is also interrupted
mentally and therefore harder to follow. This is true for me, and I believe it would be true for most people who are comfortable with written language.

For context, I am a technical editor with a background in writing and editing newsletter articles and marketing material. And as you can see, I am also a firm believer in single spaces after a period. Besides improving readability, it saves time and keystrokes!

What I find interesting here is that some people are saying it's bad because
it's antiquated. There's a funny "rule" we have that says "Don't use prepositions at the end of sentences." Well why not? It's completely arbitrary. But they still force it on us. Why? Because it's the nature of language. So, why do so many of us
still double-space between sentences? Because it's the nature of society to perpetuate practices as long as they have no ill effects.

Anyway, as far as I can tell, a ton of the confusion comes from the difference between term-paper writing and book publishing. You see, in my days in school, any paper we wrote would be left-aligned, double-spaced (line spacing), lots of header crap, centered
unadorned title, name + page numbers on all but the first page, indent every paragraph, MLA style references. Really the important point there was left-aligned. I don't recall ever having read a book that was left-aligned. They're all fully justified.
As far as writing my papers goes, Word makes absolutely no spacing decisions, other than when to word-wrap and whatever comes as part of the font. Because it's
left-aligned. If I wanted justified, I would single space. Because then things
do get wacky.

Here's some reasons I double space...

- when I search for a sentence, I rely on greater spacing (legally blind here)
- when I read something left-aligned I feel unfulfilled if it's single-spaced
- because it's the way I've always done it, and since there is nothing evil about it, there's no reason to stop now

I'd also like to affirm whoever said that everyone reads by pattern-recognition. That's actually why I'd never teach a kid by "phonics," because it just wouldn't work. But that doesn't mean we don't interperet punctuation. Like the period in illogical places,
we notice. Like a contraction with no apostrophe, wed notice. We'd read it right, but we'd notice. So to my linguistic mind, it makes perfect sense to have two spaces in left-aligned documents as a secondary end-of-thought marker. Especially if we're going
to read out loud.

Interesting thought, before I go: In books and newspapers, ever come across the line you couldn't read? I have. And it's because the spacing failed. Miserably.

On your point of never using double spaces after a full-stop, I must disagree. Other users have given several good reasons for using double spaces, all of which I agree with.

In addition, I hate reading a professionally typeset, proportionally-spaced sentence which ends with something like "Washington, D.C." and whose next sentence starts with a proper noun. Without the double-space I can't always tell if the first sentence has
ended. Just the other day I ran across such a sentence and had to stop and re-read it
three times in order to parse it correctly!

Also, if all of these great typesetting rules have stuck around for a reason (ie, they work), they why is the rule about double-spacing suddenly bad? Didn't it work for all these years? Does it have no value?

Of course, you're quite possibly correct to draw a distinction between mono-spaced and proportionally-spaced type. I think that in my case, my eye is trained to expect to see double spaces in mono type, while at the same time is used to whatever standard is
used in professional typography (single spacing, apparently). I see no reason why the two can't co-exist peacefully, esp. as a computer should be able to convert between the two. (BTW, can't typographers come up with a solution to my "...Washington, D.C.
Bush..." problem?)

Even though I'm not a typographer, I still care deeply about this stuff. You can aruge about it until you're blue in the face, but I'll need a better reason to change my habits.

Incidentally, I was taught both rules (not underlining, and using double spaces) in school. Not that that proves their correctness, mind you, but it certainly makes my worldview a little more satisfying.

Grammar has necessarily conservative conventions. Of course, conventions should be reviewed for purpose and effect. The purpose for spacing is for improved readability, or faster comprehension. As an example, youcouldstringwordswithoutspacing.
This lack of spacing between words slows comprehension, because you have to separate each word mentally. Each word represents a discrete idea. Extending this spacing concept as a method of compartmentalizing discrete ideas for faster comprehension, a period
and double-spacing aid comprehension by separating one complete thought, or sentence, from another, which gives reason to pause and consider its plausibility.

or you could get extreme (you rebel, you) and abandon grammar altogether like e e cummings and adopt a stream of consciousness just dont expect others to understand you better good luck

When considering recognition of the shapes of words, remember this "oldie but a goodie".

Did you konw taht the hmuan biran can raed wrods no mtater waht odrer the lteters are in as lnog as the fisrt and lsat lteters are croerct?

Yes, it is pattern recognition. Single and double spacing after a full stop is just a variation on this. What you are "used" to will always "the right way for me".

Habit can be your friend, and with only a little effort you can change any habit. I used to be a "two spacer", but converted. Actually it can also speed up one's typing as well. Think of all those extra space bar hits your poor thumb doesn't have to perform.

I have to admit though, the dual examples did seem to come across clearer with the two spaces. Hmmm, maybe I need to re-think my habits.

There have been many interesting arguments on both sides of the issue. What is missing is some empirical data to back up these arguments.

Does anyone know where to find a published study on the readability of single spacing versus double spacing? How does a typical audience respond to each style? Do they respond differently to spacing in printed versus online text? Has anyone performed any
actual measurements of reading time, comprehension, and audience willingness to read single-spaced versus double-spaced text?

Personally, I'm a double spacer, but I'm willing to change if someone can show me some real data "proving" that one way is better than the other.

I am a two-spacer, I also take delight in the fact that I do this:
one item, two items, and three items (note the comma before the and).

I have learned that certain aspects of the English language (quite a few actually) have, are, and will change from time-to-time). Such as the comma (,) before the
and example above! (Credit: My college Proof-reading class and my persistence to know the reason-for-the-season sort of badgering style questioning of the instructor)

Also, some experts even disagree on which syntax should be used! Yikes! It seems to be common amongst those same experts that as long as you stay consistent through out your writings, then your syntax is just fine.

I want to add that with two-spacing after a period, to me, will help when reading on a computer's monitor, LCD, etc., because there are so many different
types and that wide varying amount of types occasional presents to me, the reader, a cluttered paragraph at times.

Single-Spaced:

I love to program, repair, and use computers. Don't ask me why I like these activities. I love to program, repair, and use computers. Don't ask me why I like these activities. I love to program, repair, and use computers. Don't ask me why I like these activities.
I love to program, repair, and use computers. Don't ask me why I like these activities. I love to program, repair, and use computers. Don't ask me why I like these activities.

I love to program, repair, and use computers. Don't ask me why I like these activities. I love to program, repair, and use computers. Don't ask me why I like these activities. I love to program, repair, and use computers. Don't ask me why I like these
activities. I love to program, repair, and use computers. Don't ask me why I like these activities. I love to program, repair, and use computers. Don't ask me why I like these activities.

*Now, look over both paragraphs a few times and see how your eyes catch on the double-space at the end of the sentences in the double-spaced paragraph? I believe this also gives one's mind a tad more time to consume each sentence.

Don't forget that one can adjust spacing around each type character. (aka. Leading) and that can lead to some text that really looks like multiple run-on sentences with regards to single-spacing after a period.

*Now, look over both paragraphs a few times and see how your eyes catch on the double-space at the end of the sentences in the double-spaced paragraph? I believe this also gives one's mind a tad more time to consume each sentence.

That's exactly the problem. Or, at least, part of it. Think about it, you're applying the QWERTY logic to the very substance of
reading - 'designing in' a flaw to slow the I/O of information. Surely we want text to flow as efficiantly and smoothly as possible, Not... Make iT h@Rder and, slower , t0; reAd? Obviously it suits the way your eyes/mind works, probably because you've
just got used to it, but I'd suggest it certainly wouldn't be an approach to aspire to or standardise.

OK, this is Bill Hill. Sorry about the change of username. For some reason I couldn't connect with my old one, so I had to create a new one.

First thing to say is that I was utterly staggered and humbled to see that by now more than 140,000 people have watched this video. Thanks, everyone!

Second thing: What is a space?

If you're using a typewriter, or a monospaced font designed to emulate one, a space is a fixed size. Choose one after a period, or choose two, it's unimportant. Whatever makes you feel good and looks right to you. If you want it to look like it was typed on
a typewriter, two probably looks more authentic. In fact, you need two spaces to differentiate from the single space between words.

I was talking about proportionally-spaced fonts - which these days means most fonts on your system - in which a "wordspace" could be different in any line, depending on how much or how little the composition engine has to distribute between the words.

The designer who spent months or years designing the font you're using also took the trouble to design what he or she calculated was the optimum value of a "space".

One space after a period was what the designer envisaged. And it'll be proportional to the type size you're using. And it will be easier to read. But if you think
you know better, by all means go ahead and use two.

However, if I ever find myself editing your copy, the first thing I'll do is run Search-and-Replace to replace all the double-spaces with a single space, including all the ones between words that you never actually
meant to be double-spaces - which I've found to be the single most common typo these days.

It's easy to do, because it's sometimes hard to tell with a proportionally-spaced font that you've typed two spaces, especially at smaller sizes. But they can cause reflow problems if left in. A global S-&-R is an easy operation, so leaving them in is sloppy
and unprofessional IMO. Search-and-Replace is usually the very last thing I do on any copy, including my own, as a final cleanup.

So there's a practical reason for using only one space, too. Unless you want to step through all your spaces manually, replace only the mistakes, and keep the ones at the ends of sentences.

We are now trying to do some entity extraction from text and cannot do it easily because of the conversion to one space after a period from two. It is difficult to determine if a period is after an abbreviation vs the end of a sentence. I vote for 2 spaces
after a period if the period is ending a sentence for this very reason!

I want to use two space, I really do. But our doc and UX people shout at me when I do that, so I kind of got out of the habit. WIth all respect to Bill, his main argument is "good typographers say this and that so there". I've never actually heard a good argument for using only one space after a full stop (period).

Using two spaces is better, and it's actually important now than in the days of typewriters. Why? Because with the proportional fonts we use these days, the space is typically narrower than in monospaced fonts (where the space if obviously the full with of a character), so a single space is not as effective at giving the "that sentence is done, here's the next one" message. The full stop should do that, yes, but it's often missed or ignored as a printing artifact or mark on the screen.

It seems like a small thing but if it alters the meaning of a piece of text because the reader doesn't realise they're now looking at a different sentence then the text has failed to do its job.

I am so late to this thread, but I do want to add my $0.02 to the mix.

I was a typographer in the pre-Mac/page-layout days, and wrote with a typewriter before that. I agree with the other posters that there should be one space only after a period with just ONE exception.

Typewriters, with the exception of the IBM Selectric, required two spaces because they all were monospaced characters. The Selectric was the first with proportional fonts and required only one space. In typography I learned the rules that held for over a hundred years: Two spaces for monospaced fonts, one for proportional. When creating left-and-right-justified type, the rule was one space no matter what, because the machine varied the spaces to make the left and right sides straight and two spaces there would make it look horrible.

Now only newspapers (and not all of them) and some magazines use left-and-right justified so the original rule holds. Never use two spaces unless you are typing in Courier or equivalent and your column is left-justified. Double-justified (which we used to call simply "justified") is never, ever used in web pages except for a special effect because of how bad it looks on our low-resolution screens (compared to printed pages).